In the past few decades, the petroleum industry has invested heavily in the development of marine seismic survey techniques that yield knowledge of subterranean formations beneath a body of water in order to find and extract valuable petroleum resources. A typical marine seismic survey may be carried-out with a survey vessel towing a seismic source and the same vessel, or another vessel, towing one or more streamers that form a seismic data acquisition array below the surface of the water and above the subterranean formation. The survey vessel typically contains seismic data acquisition equipment, such as navigation control, seismic source control, seismic receiver control, and data recording equipment. The seismic source control activates a seismic source, which is typically an array of source elements, such as air guns or marine vibrators, that produces acoustic signals at selected times or at selected locations. Each acoustic signal is generally a sound wave that travels down through the body of water and into the subterranean formation. At interfaces between different types of rock, a portion of the sound wave is transmitted, a portion is refracted, and a portion is reflected back into the body of water to propagate toward the water surface. The streamers towed behind the survey vessel are elongated cable-like structures. Each streamer may include a number of seismic receivers or multi-component sensors that detect pressure and/or particle motion wavefields of the sound waves reflected back into the water from the subterranean formation. However, the wavefields measured by the receivers may also include seismic energy created by other active sources. This additional seismic energy may create seismic interference. Those working in the petroleum industry seek techniques to improve separation of seismic energy created by two or more sources.